Abstract: In certain embodiments, a device is provided that utilizes both interferometrically reflected light and transmitted light. Light incident on the device is interferometrically reflected from a plurality of layers of the device to emit light in a first direction, the interferometrically reflected light having a first color. Light from a light source is transmitted through the plurality of layers of the device to emit from the device in the first direction, the transmitted light having a second color.

Abstract: An embodiment for a pixel for a display device on a substrate is disclosed. The pixel includes a first interferometric modulator on the substrate. The first interferometric modulator has a first normal direction substantially perpendicular to the first interferometric modulator and a first angularly-dependent reflectivity function comprising a first reflectivity in a first direction and a second reflectivity in a second direction, with the first reflectivity being greater than the second reflectivity. The pixel also includes a second interferometric modulator on the substrate. The second interferometric modulator has a second normal direction substantially perpendicular to the second interferometric modulator and a second angularly-dependent reflectivity function comprising a third reflectivity in the second direction and a fourth reflectivity in the first direction, with the third reflectivity being greater than the fourth reflectivity.

Abstract: A display with a photovoltaic (PV) cells integrated as the front side and/or back side of the display is disclosed. Ambient light may reach a PV cell situated behind a display through fully or partially transmissive features within the display. Display-generated light may also reach a PV cell behind a display. A transmissive PV material situated in front of a display may collect both ambient light as well as display-generated light.

Abstract: Certain embodiments include interferometrically tuned photovoltaic cells wherein reflection from interfaces of layered photovoltaic devices coherently sum to produce an increased field in an active region of the photovoltaic cell where optical energy is converted into electrical energy. Such interferometrically tuned or interferometric photovoltaic devices (iPV) increase the absorption of optical energy in the active region of the interferometric photovoltaic cell and thereby increase the efficiency of the device. In various embodiments, one or more optical resonant cavities and/or optical resonant layers is included in the photovoltaic device to increase the electric field concentration and the absorption in the active region.

Abstract: In various embodiments described herein, a device comprises an angle turning layer disposed over a light guiding layer that is optically coupled to a photocell. A plurality of surface features is formed on one of the surfaces of the light guiding layer. The surface features can comprise facets that are angled with respect to each other. The angle turning layer can comprise diffractive features that are volume features or surface-relief features. Light incident on the angle turning layer at a first angle is turned towards the light guiding layer at a second angle and subsequently redirected at a third angle by the surface features of the light guiding layer and guided through the light guide by multiple total internal reflections. The guided light is directed towards a photocell.

Abstract: Methods, devices, and systems provide MEMS devices exhibiting at least one of reduced stiction, reduced hydrophilicity, or reduced variability of certain electrical characteristics using MEMS devices treated with water vapor. The treatment is believed to form one or more passivated surfaces on the interior and/or exterior of the MEMS devices. Relatively gentle temperature and pressure conditions ensure modification of surface chemistry without excessive water absorption after removal of sacrificial material to release the MEMS devices.

Abstract: A light collection device includes a light guide body and a plurality of spaced-apart slits. The slits are formed by undercuts in the light guide body. Sides of the slits form facets that redirect light impinging on the facets. In some embodiments, the light collection body is attached to a photovoltaic cell. Light impinging on the light collection body is redirected towards the photovoltaic cell by the slits. The photovoltaic cells convert the light into electrical energy.

Abstract: A light guide device includes a light guide body and two or more pluralities of spaced-apart slits. The slits are formed by undercuts in the light guide body. Sidewalls of the slits form facets that redirect light impinging on the facets. In some embodiments, the light guide body is attached to a light source. The light source emits light that is injected into the light guide body and the slits redirect the light out of the light guide body and towards a desired target. In some embodiments, the target is a display and a first plurality of slits directs light from the light source across the light guide body and over the face of the display. A second plurality of slits then directs light out of the light guide body and towards the display.

Abstract: Various methods are described to characterize interferometric modulators or similar devices. Measured voltages across interferometric modulators may be used to characterize transition voltages of the interferometric modulators. Measured currents may be analyzed by integration of measured current to provide an indication of a dynamic response of the interferometric modulator. Frequency analysis may be used to provide an indication of a hysteresis window of the interferometric modulator or mechanical properties of the interferometric modulator. Capacitance may be determined through signal correlation, and spread-spectrum analysis may be used to minimize the effect of noise or interference on measurements of various interferometric modulator parameters.

Abstract: A device to measure pressure is disclosed. In one embodiment, the device comprises at least one element comprising two layers separated by a space, wherein a dimension of the space changes over a variable time period in response to a voltage applied across the two layers and a measuring module configured to measure the time period, wherein the time period is indicative of the ambient pressure about the device.

Abstract: An interferometric mask covering the front electrodes of a photovoltaic device is disclosed. Such an interferometric mask may reduce reflections of incident light from the electrodes. In various embodiments, the mask reduces reflections so that a front electrode pattern appears similar in color to adjacent regions of visible photovoltaic active material.

Abstract: Devices and methods for collecting solar energy using photovoltaic material are disclosed.

Abstract: A microelectromechanical systems (MEMS) display element may include a photovoltaic structure configured to generate electric energy from incident light. In one embodiment, the display element includes a first layer that is at least partially transmissive of light, a second layer that is at least partially reflective of light, and a photovoltaic element that is formed on the first layer or the second layer or formed between the first layer and the second layer. The second layer is spaced from the first layer and is selectably movable between a first position in which the display element has a first reflectivity and a second position in which the display element has a second reflectivity. The first reflectivity is greater than the second reflectivity. The photovoltaic element is at least partially absorptive of light and is configured to convert a portion of the absorbed light into electric energy, at least when the second layer is in the second position.

Abstract: A dimming mirror comprises an array of interferometric light modulators is disclosed. In one embodiment of the invention, the dimming mirror comprises a plurality of interferometric light modulators and a control circuit adapted to configure the plurality of interferometric light modulators to at least one of a plurality of predefined states, including a first state having a substantially reflective appearance and a second state having a dimmed visual appearance as contrasted with the first state. Additional features may include additional states having an appearance with a dimmed visual appearance as contrasted with the first state and a reflective appearance as contrasted with the second state.

Abstract: An interferometric mask covers reflective conductors on the back side of a photovoltaic device. Such an interferometric mask may reduce reflections of incident light from the conductors. In various embodiments, the mask reduces reflections, so that a front and back electrode pattern appears black or similar in color to surrounding features of the device. In other embodiments, the mask may modulate reflections of light such that the electrode pattern matches a color in the visible spectrum.

Abstract: A transmissive micromechanical device includes a substrate, an optical stack over the substrate and a moveable membrane over the optical stack. The moveable membrane may include a partially reflective mirror and be configured to move from a first position to a second position. When the movable membrane is in the first position the transmissive micromechanical device is configured to pass light of a predetermined color and when the movable membrane is in the second position, the micromechanical device is configured to block substantially all of light incident on the substrate.

Abstract: Various methods are described to characterize interferometric modulators or similar devices. Measured voltages across interferometric modulators may be used to characterize transition voltages of the interferometric modulators. Measured currents may be analyzed by integration of measured current to provide an indication of a dynamic response of the interferometric modulator. Frequency analysis may be used to provide an indication of a hysteresis window of the interferometric modulator or mechanical properties of the interferometric modulator. Capacitance may be determined through signal correlation, and spread-spectrum analysis may be used to minimize the effect of noise or interference on measurements of various interferometric modulator parameters.

Abstract: An interferometric mask covering a reflective conductive ribbon that electrically interconnects a plurality of photovoltaic cells is disclosed. Such an interferometric mask may reduce reflections of incident light from the conductors. In various embodiments, the mask reduces reflections, so that a front and back electrode pattern appears black or similar in color to surrounding features of the device. In other embodiments, the mask may modulate reflections of light such that the electrode pattern matches a color in the visible spectrum.

Abstract: Disclosed are methods and systems for testing MEMS devices (e.g., interferometric modulators) so as to induce a moveable element to move from a first position to a second position and to detect the movement. The methods include applying an electrical current to the movable element in the presence of a magnetic field, thereby producing a Lorentz force on the movable element. The force required to move the movable element from the first position to the second position can then be estimated based on the magnitudes and geometric relationships of the electrical current and the magnetic field, and the geometry of the movable element. In some embodiments, the first position may be a movable element adhered to another surface (e.g., a layer on a substrate) due to stiction forces. In these embodiments, the stiction forces can be estimated.

Abstract: In various embodiments described herein, a device comprising a light guiding layer optically coupled to a photocell is described. A plurality of surface features are formed on one the surface of the light guiding layer. The surface features can comprise facets that are angled with respect to each other. Light incident on the surface of the light guide is redirected by the surface features and guided through the light guide by multiple total internal reflections. The guided light is directed towards a photocell.